Ethernet connectivity fault management (ETH-CFM)

The IEEE and the ITU-T have cooperated to define the protocols, procedures and managed objects to support service based fault management. Both IEEE 802.1ag standard and the ITU-T Y.1731 recommendation support a common set of tools that allow operators to deploy the necessary administrative constructs, management entities and functionality, Ethernet Connectivity Fault Management (ETH-CFM). The ITU-T has also implemented a set of advanced ETH-CFM and performance management functions and features that build on the proactive and on demand troubleshooting tools.

CFM uses Ethernet frames and is distinguishable by ether-type 0x8902. In specific cases, the different functions use a reserved multicast Layer 2 MAC address that could also be used to identify specific functions at the MAC layer. The multicast MAC addressing is not used for every function or in every case. The Operational Code (OpCode) in the common CFM header is used to identify the PDU type carried in the CFM packet. CFM frames are only processed by IEEE MAC bridges.

IEEE 802.1ag and ITU-T Y.1731 functions that are implemented are available on the SR and ESS platforms.

This section of the guide provides configuration examples for each of the functions. It also provides the various OAM command line options and show commands to operate the network. The individual service guides provide the complete CLI configuration and description of the commands to build the necessary constructs and management points.

Table: ETH-CFM acronym expansions lists and expands the acronyms used in this section.